<template>
	<view>
		<!-- //使用自定义搜索组件 -->
		<my-search @click="gotoSearch"></my-search>
	<view class="scroll-view-container">
		<!-- 左侧滑动区域 -->
		<scroll-view class="left-scroll-view" scroll-y="true" :style="{height:wh+'px'}">
			<block v-for="(item,index) in cateList" :key="index">
				<view @click="activeChanged(index)" 
				:class="['left-scroll-view-item',index===active?'active':'']" >{{item.cat_name}}</view>
			</block>
		</scroll-view>
		<!-- 右侧滑动区域 -->
		<scroll-view scroll-y="true" :style="{height:wh+'px'}" :scroll-top="scrollTop">
			<view class="cate-lv2" v-for="(item2,i2) in cateLevel2" :key="i2">
				<!-- 二级分类的标题 -->
				<view class="cate-lv2-title">/{{item2.cat_name}}/</view>
				<!-- 当前二级分类下的三级分类列表 -->
				<view class="cate-lv3-list">
					<view class="cate-lv3-item" v-for="(item3,i3) in item2.children" 
					:key="i3" @click="gotoGodsList(item3)">
						<!-- 三级分类的图片 -->
						<image :src="item3.cat_icon" ></image>
						<!-- 三级分类的文本 -->
						<text class="cate-lv3-tete">{{item3.cat_name}}</text>
					</view>
				</view>
			</view>
		</scroll-view>
	</view>
</view>
</template>

<script>
	import badgeMix from '@/mixins/tabbar-badge.js' 
	export default {
		mixins:[badgeMix],
		data() {
			return {
				//当前设备可用的高度
				wh: 0,
				cateList:[],
				active:0,
				cateLevel2:[],
				scrollTop:0
			};
		},
		onLoad(){
			const sysInfo = uni.getSystemInfoSync()
			this.wh = sysInfo.windowHeight
			
			this.getCateList()
		},
		methods:{
			//获取分类列表数据
			async getCateList(){
				const {data:res} = await uni.$http.get('/api/public/v1/categories')
				if(res.meta.status !== 200) return uni.$showMsg()
				this.cateList = res.message
				//为二级分类赋值
				this.cateLevel2 = res.message[0].children
			},
			//选项中改变事件处理函数
			activeChanged(index){
				this.active = index
				//为二级分类重新赋值
				this.cateLevel2 = this.cateList[index].children
				//让scrollTop的值在0与1之间切换
				this.scrollTop = this.scrollTop===0?1:0
			},
			//跳转到商品列表页面
			gotoGodsList(item3){
				uni.navigateTo({
					url:'/subpkg/goods_list/goods_list?cid=' + item3.cat_id
				})
			},
			gotoSearch(){
				uni.navigateTo({
					url:'/subpkg/search/search'
				})
			}
		}
	}
</script>

<style lang="scss">
.scroll-view-container{
	display: flex;
	.left-scroll-view{
		width: 120px;
	}
}
.left-scroll-view-item{
	background-color : #f7f7f7;
	line-height:60px;
	text-align:center;
	font-size: 12px;
	&.active{
		background-color: #fefefe;
		position: relative;
		&::before{
			content: '';
			display: block;
			width: 3px;
			height: 30px;
			background-color: #c00000;
			position: absolute;
			top: 50%;
			left: 0;
			transform: translateY(-50%);
		}
	}
}
.cate-lv2-title{
	font-size: 24rpx;
	font-weight: bold;
	text-align: center;
	padding: 15rpx 0;
}
.cate-lv3-list{
	display: flex;
	flex-wrap: wrap;
	
}
.cate-lv3-item {
	width: 33.33%;
	display: flex;
	flex-direction: column;
	justify-content: center; 
	align-items: center;
	margin-bottom: 10px;
}
.cate-lv3-item image{
		width: 60px;
		height: 60px;
}
.cate-lv3-tete{
	font-size: 10px;
}
</style>
